login
A239111
Smallest Pell number (see A000129) divisible by n-th prime.
2
2, 12, 5, 70, 13860, 169, 408, 15994428, 93222358, 29, 107578520350, 6625109, 2378, 24580185800219268, 143263821649299118, 7645370045, 15994428, 259717522849, 37774750930342781945186508, 220167382952941249990598278, 21300003689580, 3166815962, 50305164660422142002238655969020
OFFSET
1,1
LINKS
J. L. Schiffman, Exploring the Fibonacci sequence of order two with CAS technology, Paper C027, Electronic Proceedings of the Twenty-fourth Annual International Conference on Technology in Collegiate Mathematics, Orlando, Florida, March 22-25, 2012.
MAPLE
p:= proc(n) p(n):=`if`(n<2, n, 2*p(n-1)+p(n-2)) end:
a:= proc(n) local k, t; t:= ithprime(n);
for k while irem(p(k), t)>0 do od; p(k)
end:
seq(a(n), n=1..23); # Alois P. Heinz, Mar 28 2014
MATHEMATICA
p[n_] := p[n] = If[n<2, n, 2*p[n-1] + p[n-2]]; a[n_] := With[{t = Prime[n]} , For[k=1, Mod[p[k], t] > 0, k++]; p[k]]; Table[a[n], {n, 1, 23}] (* Jean-François Alcover, Feb 14 2016, after Alois P. Heinz *)
CROSSREFS
Cf. A120947.
Sequence in context: A155892 A286480 A286256 * A112100 A079080 A228454
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Mar 27 2014
STATUS
approved